The present invention relates generally to videoconferencing services in which video and audio signals of at least one of the parties of a videoconference are transmitted to and received by at least one other party of the videoconference.
In many videoconferences, one of the parties is the xe2x80x9chost,xe2x80x9d who is typically the center or focus of the videoconference, and the other parties are the xe2x80x9cparticipants.xe2x80x9d For example, the host can be a teacher located in one classroom, and the participants can be students located in a remote classroom. Although there are several techniques that can be used to connect the host with the participants, many of these techniques limit the type of host-participant interaction and/or the number of parties that can participate in the videoconference.
In one videoconferencing technique, the video and audio signals of the host are broadcast to each of the participants. This technique finds particular application in mass broadcasting, such as when a host is delivering a lecture to a large number of participants, because there is virtually no limit on the number of parties that can participate in the videoconference. Since the host does not receive video and audio signals from any of the participants, one disadvantage associated with this technique is that there is no interaction between the host and the participants. In a modified version of this technique, the host can receive video and audio signals from a selected participant. Although this modified technique allows the host to interact with one participant, the other participants to the videoconference do not receive the video and audio signals of the selected participant and are, therefore, excluded from the interaction.
To address this problem, another videoconferencing technique has been developed in which the video and audio signals of the host and each of the participants are combined and presented to each of the parties of the videoconference. For example, in a videoconference with a host and three participants, the image transmitted to each of the parties can be a four-quadrant image with the video signal of each participant shown in a respective quadrant. While this videoconferencing technique allows each party of the videoconference to interact with one another, the number of parties that can participate in the videoconference is limited to the number of parties that can be displayed in the transmitted image (four in the example given above).
There is, therefore, a need for an improved videoconferencing system and method for connecting a host with a plurality of participants.